溴氰虫酰胺对小菜蛾的田间防效及其在花椰菜中的残留与消解动态

通过田间试验研究了溴氰虫酰胺对小菜蛾的田间防效，分析了露地栽培条件下溴氰虫酰胺在花椰菜上的消解动态和最终残留情况。结果表明:田间药效试验中10%溴氰虫酰胺可分散油悬浮剂按推荐高剂量（有效成分21 g/hm2）施药后24 h~7 d对小菜蛾的防效为92.8%~98.3%；按2倍推荐高剂量（有效成分42 g/hm2）施药，溴氰虫酰胺在花椰菜上的消解半衰期为3.86 d，其残留超标风险与田间用药量、用药次数正相关。建议生产中采用10%溴氰虫酰胺可分散油悬浮剂以有效成分21 g/hm2的剂量用药，每季最多施药2次，露地栽培条件下花椰菜上安全间隔期为3 d。

Efficiency of cyantraniliprole on Plutella xylostella (L.) and its residual dissipation dynamics in Brassica oleracea

The efficiency of cyantraniliprole on Plutella xylostella was studied, and the residue dissipation dynamics of cyantraniliprole in Brassica oleracea was analyzed. According to the research result, a safe application method of this insecticide was developed to provide a guideline for the application of cyantraniliprole in the field. Field trials by different doses indicated that 10% cyantraniliprole OD at the available dosage of 21 g/hm² had good control effect (92.8%-98.3%) from 24 h to 7 d after the application of the pesticide. The results of residue tests showed that the half-life of cyantraniliprole in B. oleracea was 3.86 d when the 10% cyantraniliprole OD was applied once at double recommended dosages (42 g a.i./hm²). The residue risk in the harvested B. oleracea was positively correlated with application dose and spraying frequencies. The safety interval was suggested to be 3 d in the open field if the recommended dosages (21 g a.i./hm²) was applied no more than 2 times.